Staple feed mechanism for fastener applying instruments



30,1941. y QATTULA 2,268,102

STAPLE FEED MECHANSM FOR FASTENER APPLYING INSTRUMENTS v Filed May s1,1941 INVENTOR OTTO ATT ULA ATTORNEYS Patented Dec. 30,1941

UNITED STATE STABLE zasaioz FEED MECHANISM FOR FASTENER v APPLYINGINSTRUMENTS om. anula, Woodside N. Y., assigner to Lou Obstfeld,Brooklyn, N. Y., and Abraham Obstfeld, New York, N. Y.

Application May 31, 1941, serial No. 395,383.

13 Claims.

This invention relates to fastener applying instruments of the magazinetype, and-,more

.particularly to the feed mechanism for such4 and the feed mechanism isaccordingly made removable. It comprises a staple pusher, a rod slidablyreceiving the pusher, a feed spring coiled about the rod, and a pusherlocked affixed to the rear end of the rod. One object of the presentinvention isto improve the pusher lock 4and to make the same openlyaccessible and readily releasable. Another object is to facilitateloading the machine with staples, and for this purpose the staple coremay be projected beyond the rear end of the frame of the machine, theprojecting end'preferably being housed and concealed by the aforesaidpusher lock. Still another object is to facilitate replacement of thefeed mechanism by preventing rotation of the pusher and the pusher lockrelative to the aforesaid rod, the pusher being keyed to the Thefastener applying instrument is of the rear-loading type,

Fig. 6 illustrates the keyways on the pusher for receiving the keyed end`of the rod;

Fig. 7 is a plan view of the keyed end of the rod; Y 4

Fig. 8 is a side elevation of the keyed end of the rod;

Fig. 9 is a transverse section through the staple magazine with `thefeed mechanism removed;

Fig. 10 is a plan view of the rear end of the fastener applyinginstrument, corresponding substantially to the part of the machine shownin Fig. 2; and

Fig. 11 is a partial section through the rear end portion of a machinehaving a modified pusher lock. l

Referring to the drawing, and more particularly to Fig. 1, the completefastener applying rod by tapered or wedge-shaped keys which v .insureautomatic engagement of the parts in keyed relation.

To the accomplishmentof the foregoing and such other objects as willhereinafter appear, my invention consists in the elements of thefastener applying instrument and their relation one to the other, ashereinafter are more particularly described in the specification andsought to be defined in the claims. is accompanied by a drawing, inwhich:

Fig. 1 is a section taken in elevation through a fastener applyinginstrument embodying features of my invention, (the upwardly turnededges of the sides' of the machine being crosshatchedfcr clarity, asthough the section were somewhat 0E true center line);

Fig. 2 shows the rear end portion of the machine in elevation;

Fig. 3 is a horizontal section taken in the plane of the line 3-3 ofFig. 2;

Fig. 4 is a similar view (with only part of the pusher lock broken away),but showing how the sides of the pusher may be pressed together torelease the detents;

Fig. 5 is a side elevation showing replacement of the staple pusherafter loading the machine with staples:

The specification instrument comprises a frame I2, part of whichconstitutes a grip i4. The frame consists of sides having edges benttoward one another to forma structure which is enclosed except at thebottom, where appropriate staple magazine parts areinserted; and at theforward and rear ends l of the staple magazine, the latter being readilyopenable for rear loading of staples, and the forward end being openablefor servicing and for the relief of staple jams. In the present case,the .fastener applying instrument is a tacker, and no anvil or stapleclincher is prof vided.

. The machine is operated by means of a handle I6 pivotedat I8, andcarrying a pawl `2l). The staples are driven by a staple driving blade22 secured .to a plunger 24 urged downwardly by a main drive spring 26.Leather inserts 28 and 28 may, if' desired, be provided at the top ofspring 26 andbeneath plunger 24. When handle I6 `is depressed, thespring 26 is compressed until pawl 20 reaches and bears against a pawlrelease pin 30 which moves the pawl rearwardly and so releases theplunger for descent, at which time it drives the -endmost one of a barof staples 32 out of the machine. When handle i6 is released, it'israised by a'restoring spring 3l, and the upward motion may be limited bya stop 36 secured to and forming a part of handle i6. I

The staple magazine comprises a staple core 38 which is dimensioned toslidably receive the staples. The rear end 40 of the staple coreprojects beyond the open rear end 42 of the frame, and is preferablytapered as shown, in order to facilitate the staple-loading operation.The staple core 38 is properly spaced from the sides to be receivedwithin the sides of the frame, and

my invention in several preferred forms, changes and modifications maybe made in the structures disclosed, without departing from the spiritof the invention as sought to be defined in the following claims.

I claim:

1. Staple feed mechanism for a magazine type mating detent means formedon the sides of the of fastener applying mechanism having side walls.

said mechanism including y a staple pusher, a pusher spring, and apusher lock at the rear end of said spring, said lock comprising -sidewalls which partially overlap the sidewalls of the instrument, andmating detent means formed -on said overlapping side walls, thearrangement being such that the lock may be secured in position bysimply pushing it into place, and may be removed by pressing the exposedsides of the lock together in order to release the mating detent means.

2. Staple feed mechanism for a magazine type of fastener applyinginstrument having side walls, said mechanism including a staple pusher,a pusher spring, and a` pusher lock at-the rear end of said spring, saidlock comprising side walls which are received partially within the sidewalls of the instrument, and mating detent means formed on saidoverlapping side walls, the arrangement being such that the lock may besecured in position by simply pushing it into place, and may lbe removedby pressing the exposed sides of the lock together in order to releasethe mating detent means.

3. Staple feed mechanism for a magazine type of fastener applyinginstrument having side walls, said mechanism including a staple pusher.a rod slidably receiving said pusher, a pusher' spring coiled about saidrod, and a pusher lock at the rear end of said rod, said lock comprisingan end wall to which the rod is secured and side walls bent forwardlyfrom and formed integrally with said end wall, said side walls beingreceived partially within the side walls of the instrument, and matingdetent means formed on the overlapping side walls, the arrangement beingsuch lthat the lock lmay be secured in position by simply pushing itinto place, and .may be removed by. pressing the exposed sides ofthelock together in order to release the mating detent means. f

4. Staple feed mechanism for a magazine type of fastener applyinginstrument having side walls, said mechanism including a staple pusher,a rod slidably receiving said pusher, a pusher spring coiled about saidrod, and a pusher lock at the rear end of said rod, said lock comprisingan end wall to which the rod is secured and sideA walls bent forwardlyfrom and formed integrally with said end wall, detents formed on saidside walls and dimensioned to be received within the adjacent side wallsof the instrument, said instrument walls having mating recessestoreceive said detents, the arrangement being such that the lock may besecured in position by simply pushing it into place, and may be removedby pressing the exposed sides of the lock together in order to releasethe detents from the recesses. i

5. In a fastener applying instrument comprising a frame including sidewalls open at the rear end, a feed mechanism including a staple pusher,a feed spring, and a pusher lock mounted at the rear end of said spring,said pusher lock comprising a piece of sheet metal bent to form ahousing open at the forward end and dimensioned to close the lopen rearend of the frame, tabs projecting forwardly from the sides of thehousing frame and tabs for holding the parts together,

said detent means being releasable by pressing open at the forward endand dimensioned to close the open rear end oi the frame, the sides ofsaid housing being pressed outwardly to form buttons which facilitatesqueezing the sides of the housing together, tabs' projecting forwardlyfrom the sides of the housing to be received within the formed on thesides of the frame and tabs for holding the parts together, saidl detentmeans being releasable by pressing together thesides of the housing. Y

7. In a fastener applying instrument comprising a frame including sidewalls open at the rear end, a feed mechanism including a staple pusher,a rod slidably receiving saidpusher, a feed spring coiled about saidrod, and a pusher lock mounted at the rear end of said rod, said pusherlock comprising a piece of sheet metal `bent to form a housing which isclosed at the rear end and open at the forward end and dimensioned toclose the open rear end of the frame, said rod being secured to theclosed rear end` of the housing, the sides of the housing beingdimensioned to be received partially within the sides of the frame, andmating detent means vformed -on the overlapping sides of the frame andtabs for holding the parts together, said detent means being releasableby pressing together the exposed sides of the housing.

8. In a fastener applying instrument'comprising a frame including sidewalls open at the rear end; a staple core disposed in said fastenerandhaving a. rear end which projects beyond the sides of the fastener tofacilitate the loading of staples. in the machine, a feed mechanismincluding a staple pusher, a rod slidably receiving said pusher, a feedspring coiled about said rod, and a pusher lock mounted at the rear endof said rod, said pusher lock comprising apiece of sheet metal bent toform a housing open at the forward end and dimensioned to be receivedover and to enclose the exposed rear end of the staple core, the sidesof the housing being dimensioned to be received partially within thesides of the frame, and mating detent means formed on the overlappingsides of the frame and housing for 'said pusher, a feed spring coiledabout said rod,

and a pusher lock mounted at the rear end of said rod, said pusher lockcomprising a piece of sheet metal bent to form a housing open at theforward end and dimensioned to be received over and to enclose theexposed rear end of the staple core, the sides of said housing beingpressed outwardly to form buttons which facilitate squeezing d: lacceden er, a feed spring coiled about said rod for urging the pusherforwardly, and means to x the pusher against rotation on the rod whenthcpusher is removed from the instrument, said means including keywaysformed on the pusher and keys formed at the end of the rod, said keysbeing tapered or Wedge-shaped with the large end of the wedge toward theforward end of the rod and the pointed end of the vWedge toward theVrear end of the rod, whereby said keys readily move into said keyways,yet said pusher cannot leave the rod entirely..

11. Staple feed mechanism for a fastener applying instrument, saidmechanism comprising a pusher, a round rod slidably receiving saidpusher,` a feed spring coiled about said rod for urging the pusherforwardly against the staples. a pusher lock non-rotatably secured tothe rear end or' said rod, and means to x the pusher against rotation onthe rod when the pusher is removed from the instrument, said meansincluding keyways formed on the pusher andkeys formed at the end of. therod, andA said keys being tapered or wedge-shaped with the large end ofthe Wedge toward the forward end of the rod and the pointed end of theWedge toward the rear end of the rod, whereby said keys 4readily moveinto said keyways, yet saidv pusher cannotleave the rod entirely. i l

12. in a fastener applying instrument comprising a frame which is vopenat the rear end, a feed mechanism including a staple pusher, a .feedspring, and a pusher lock at the rear end of Saidv spring, said pusherlock comprising a piece of sheet metal bent to form a housing open atthe forward end and dimensioned to close the open rear end of the frame,a wall of said housing projecting forwardly to overlap a wall of theframe, and mating detent means formed on the overlapping parts of theframe and housing walls for holding the pusher lock a`nd the frametogether, said detent means being releasable by pressing an exposed partof the housing wall.

13. In a fastener applying instrument comprising a frame which is openat the rear end, a feed mechanism including a staple pusher, a 'feedspring, and a pusher lock at the rear end of said spring, said pusherlock comprising a piece of sheet metal bent to form a housing open atthe forward end and dimensioned to close the open rear end of theframe,l a wall of said housing projecting forwardly to be receivedwithin a wall of the frame, the exposed part of said housing wail beingpressed outwardly to form a convex button to facilitate squeezing. thehousing wall away from the frame wall, and mating detent means formed onthe overlapping parts of the frame and housing walls for holding thepusher lock and the frame together, said detent means being releasableby pressing the aforesaid button.

OTTO ATTULA.

